Comparison of Tomato Growth and Yield according to Solar Radiation by Location in Multi-span Greenhouses

To examine the distribution of internal solar radiation within various locations in multi-span greenhouses, the solar radiation, light transmittance, and accumulated radiation at the central and lateral sections were analyzed by dividing 8:30 to 12:30 in the morning and 12:35 to 16:30 in the afternoon.The growth and yield of tomatoes within these sections were also compared.In the morning, the solar radiation of the central section and the side section was 275.2 W•m -2 and 314.9 W•m -2 , while in the afternoon, it was 314.9 W•m -2 and 313.9 W•m -2 , respectively.The light transmittance and accumulated radiation were also low, confirming the low distribution of solar radiation in the central (connecting) section of the multi-span greenhouses.The growth survey revealed no significant difference.The final yield of tomatoes per plant was 4,828 g in the central section and 4,851 g in the lateral section, but there was no significant difference in the central section compared to the lateral section by 0.5%.However, the amount of solar radiation as per time in the central section is higher than the light compensation point, 60 W•m -2 , and slightly lower than the light saturation point of tomatoes, i.e., 281 W•m -2 .The results of this study can help in greenhouse design based on the insolation environment.